The instant invention is directed to salts of di-perfluoroalkyl group containing acids with ammonia or amines, and the manufacture and use of such salts in the form of aqueous emulsions or dispersions in treating cellulosic materials and natural polyamide materials to render the same oil and water repellent.
Di-perfluoroalkyl group containing acids, useful as starting materials in the manufacture of the instant ammonium and amine salts, are, in part, disclosed in U.S. Pat. No. 4,239,915, the disclosure of which is incorporated by reference herein. The di-perfluoroalkyl group containing acids are disclosed therein as useful inter alia for textile treating or as chromium complexes which possess oil and water repellent properties and are indicated as useful as grease or oil repellents for paper. Unfortunately, these acids possess, in general, very limited water solubility and therefore require an organic solvent, or the like, for the application of the di-perfluoroalkyl group containing acids to the cellulose, synthetic or natural polyamide substrate in order to obtain the desired oil and water repellent properties. Such organic solvent containing solutions of the di-perfluoroalkyl group containing acids tend to be expensive due to the cost of such organic solvents. Moreover, the use of such organic solvent containing systems is often undesirable due to odor, toxicity and flammability hazards. Furthermore, such organic solvent containing systems tend to be inefficient since much of the fluorochemical tends to remain in the organic solvent system during the application process and must be subsequently recovered from the spent organic solvent liquor for re-use. Also environmental problems are usually inherent in the use of organic solvent systems on an industrial scale.
It is an object of the present invention to avoid such problems by providing to the artisan ammonium and amine salts of di-perfluoroalkyl group containing acids. The ammonium and amine salts of the present invention are conveniently prepared by reacting the corresponding di-perfluoroalkyl group containing acids with ammonia or the amine in a diluent substantially inert to the acid and ammonia or amine reactants, and recovering the amine salt formed. As the reaction between the ammonia or amine and the acid takes place spontaneously, the reaction can be conducted at temperatures between 0.degree. C. and 100.degree. C., preferably at ambient temperature conditions. Where the amine is introduced in gaseous form, such as anhydrous ammonia or methyl amine, it can be bubbled through the acid in the liquid diluent medium. As the reaction tends to be exothermic, cooling of the reaction vessel may be advantageously employed. Where the inert diluent is organic in nature, such as a lower alkanol, for example methanol, isopropanol, or the like, the ammonium or amine salt reaction product can be recovered by precipitation, or evaporation of the diluent. If the inert diluent is water, the ammonium or amine salt need not be separated from the aqueous media.
Where the amine is a quaternary ammonium compound, the resulting salt may be obtained by adding together in the inert diluent, such as water, the di-perfluoroalkyl group containing acid with the quaternary ammonium compound in the base, or hydroxide form. Alternatively, the di-perfluoroalkyl group containing acid may be neutralized with alkali or alkaline earth metal base, and the metal salt reacted with the quaternary ammonium compound in the halide form in an inert diluent by double displacement and the inorganic salt optionally separated therefrom by known extraction or precipitation techniques.
It is a further object of the invention to provide to the artisan aqueous emulsions and dispersions of the ammonium and amine salts which avoid the application problems associated with organic solvent containing systems.
It is a further object of the present invention to provide the artisan with efficient fluorochemical dispersions and emulsions providing high fluorochemical pick-up properties on cellulosic and natural polyamide substrates.
It is a further object of the present invention to provide the artisan with fluorochemical treated cellulosic and natural polyamide containing materials possessing a high degree of oil and water repellent properties, and a method of making the same.
These and other objects of the invention are apparent from the foregoing disclosure.